No one who judges of it only on the basis of outward appearances can know that there is any evil in adultery; for in outward appearances it bears a resemblance to marriage. When internal qualities are mentioned, and those superficial judges are told that external actions draw their goodness or evil from them, they say to themselves, "What are internal qualities? Who sees them? Is this not something that transcends the realm of anyone's intelligence?" Such people are of the same character as those who accept all affected good as genuine and sincere, and who estimate a person's wisdom in accordance with the elegance of his speech. Or they are like those who esteem the man himself in accordance with the fineness of his clothing and the grandness of the carriage in which he rides, and not in accordance with his inner deportment, which has to do with his judgment arising from his affection for good. It is also comparable to judging of a tree's fruit or any provender simply by its look and feel, and not considering its goodness by the way it tastes and what one knows about it. Thus do all do who are averse to discerning anything of a person's internal qualities. From this originates the madness of many today, that they do not see anything evil in adulterous affairs - indeed, that they put marriage and adultery together in the same bed, in other words, make them alike; and this simply because of their seeming similarity in outward appearances. [2] I was convinced of the fact of this by the evidence of the following experience: Some angels once called together several hundred people from the European world, of those distinguished for their genius, learning and wisdom there; and they questioned them about the difference between marriage and adultery, asking them to consult the rational considerations of their intellect. After consulting then, all but ten replied that statutory law alone makes a distinction, and this for the sake of some beneficial end, an end which can indeed be defined, but yet be accommodated through judicial discretion. The angels next asked them whether they saw anything good in marriage or anything evil in adultery. They replied that they saw no rational evil or good. When asked whether they saw anything sinful in the latter, they said, "In what respect? Is not the act the same?" The angels were stunned at these responses and exclaimed, "Oh, how extraordinary and how great the grossness of the age!" When they heard that, the hundreds of the wise assembled turned around and guffawing said to each other, "Is this grossness? What possible wisdom is there to convince us that to make love to another's wife is deserving of eternal damnation?" [3] Adultery, however, is a spiritual evil, and therefore a moral evil and a civil evil, diametrically opposed to the wisdom of reason. The love in adultery also ascends from hell and descends back to it, while the love in marriage descends from heaven and ascends back to it. This we showed at the outset of this second part, in the chapter on the opposition of licentious love to conjugial love.* But because all evils, like all goods, are allotted a breadth and a height, and because according to that breadth they have their kinds and according to that height their degrees, therefore in order that adulteries may be distinguished in respect to both dimensions, we will divide them first into their kinds and afterwards into their degrees. This we will do according to the following outline:

(1) There are three kinds of adultery: simple adultery, double adultery, and triple adultery. (2) Simple adultery is the adultery of an unmarried man with the wife of another, or of an unmarried woman with the husband of another. (3) Double adultery is the adultery of a married man with the wife of another, or vice versa. (4) Triple adultery is adultery with close blood relatives. (5) There are four degrees of adultery, which affect accordingly subsequent attributions of it, convictions, and, after death, imputations. (6) Adulteries of the first degree are adulteries of ignorance, which are committed by people who are not yet able to or cannot consult the intellect and so prevent them. (7) Adulteries committed by such people are mild. (8) Adulteries of the second degree are adulteries of lust, which are committed by people who are indeed able to consult the intellect, but for reasons of circumstance at the moment cannot. (9) Adulteries committed by such people are imputable to them according as their intellect afterwards sanctions them or does not sanction them. (10) Adulteries of the third degree are adulteries of the reason, which are committed by people who intellectually persuade themselves that they are not sinful evils. (11) Adulteries committed by such people are grave and are imputed to them in accordance with their persuasions. (12) Adulteries of the fourth degree are adulteries of the will, which are committed by people who make them allowable and pleasurable, and not of sufficient consequence to merit consulting the intellect in regard to them. (13) Adulteries committed by such people are the most grave and are imputed to them as purposeful evils, and they become settled in them as culpable offenses. (14) Adulteries of the third and fourth degree are sinful evils according to the measure and nature of the intellect and will in them, whether they are committed in act or not. (15) Purposeful adulteries arising from the will, and deliberate adulteries arising from a persuasion of the intellect, render a person natural, sensual and carnal. (16) And this to the point that they finally cast away from them everything having to do with the church and religion. (17) Nevertheless, they still possess human rationality like others. (18) Yet they use their rationality only when engaged in their outward lives, but abuse it when engaged in their inner ones.

Explanation of these statements now follows. * Nos. 423ff.